No abstract

Size and abundance data were compiled and collated for blue cod Parapercis colias and rock lobster Jasus edwardsii from New Zealand marine reserve (MR) studies for a meta-analysis to test the null hypotheses that reserve status does not affect the size or abundance of either species. Calculation of meta-analysis effect sizes revealed that significant differences in effect size existed among studies, meaning that the biological response to MR status of both species in terms of their changes in size and/or abundance differed significantly among the MRs. Analysis revealed that blue cod were bigger inside compared with outside MRs in 9 of 10 studies and were more abundant inside MRs in 8 of 11 studies, and that rock lobster were bigger inside the MRs in 12 of 13 studies and more abundant inside the MRs in 11 of 14 studies. These findings indicate that MR protection can result in more and bigger individuals soon after the establishment of the MR (mean of 6.5 yr for blue cod, 8.5 yr for rock lobster) despite small sample sizes of studies (≤10 for blue cod, ≤14 for rock lobster). Focused comparison tests did not reveal any relationship between rock lobster or blue cod size or abundance and either age or area of MRs. Our results demonstrate that no-take MRs are valuable conservation tools for species such as blue cod and rock lobster (and probably also for other exploited species with similar life history characteristics and habitat requirements) and that statistically detectable conservation benefits are apparent after only a few years of protection.

The marine-biodiversity assessment of New Zealand (Aotearoa as known to Māori) is confined to the 200 nautical-mile boundary of the Exclusive Economic Zone, which, at 4.2 million km2, is one of the largest in the world. It spans 30° of latitude and includes a high diversity of seafloor relief, including a trench 10 km deep. Much of this region remains unexplored biologically, especially the 50% of the EEZ deeper than 2,000 m. Knowledge of the marine biota is based on more than 200 years of marine exploration in the region. The major oceanographic data repository is the National Institute of Water and Atmospheric Research (NIWA), which is involved in several Census of Marine Life field projects and is the location of the Southwestern Pacific Regional OBIS Node; NIWA is also data manager and custodian for fisheries research data owned by the Ministry of Fisheries. Related data sources cover alien species, environmental measures, and historical information. Museum collections in New Zealand hold more than 800,000 registered lots representing several million specimens. During the past decade, 220 taxonomic specialists (85 marine) from 18 countries have been engaged in a project to review New Zealand's entire biodiversity. The above-mentioned marine information sources, published literature, and reports were scrutinized to give the results summarized here for the first time (current to 2010), including data on endemism and invasive species. There are 17,135 living species in the EEZ. This diversity includes 4,315 known undescribed species in collections. Species diversity for the most intensively studied phylum-level taxa (Porifera, Cnidaria, Mollusca, Brachiopoda, Bryozoa, Kinorhyncha, Echinodermata, Chordata) is more or less equivalent to that in the ERMS (European Register of Marine Species) region, which is 5.5 times larger in area than the New Zealand EEZ. The implication is that, when all other New Zealand phyla are equally well studied, total marine diversity in the EEZ may be expected to equal that in the ERMS region. This equivalence invites testable hypotheses to explain it. There are 177 naturalized alien species in New Zealand coastal waters, mostly in ports and harbours. Marine-taxonomic expertise in New Zealand covers a broad number of taxa but is, proportionately, at or near its lowest level since the Second World War. Nevertheless, collections are well supported by funding and are continually added to. Threats and protection measures concerning New Zealand's marine biodiversity are commented on, along with potential and priorities for future research.

No abstract

Aim Sufficient data to describe spatial distributions of rare and threatened populations are typically difficult to obtain. For example, there are minimal modern offshore sightings of the endangered southern right whale, limiting our knowledge of foraging grounds and habitat use patterns. Using historical exploitation data of southern right whales (SRW), we aim to better understand their seasonal offshore distribution patterns in relation to broad-scale oceanography, and to predict their exposure to shipping traffic and response to global climate change.Location Australasian region between 130°W and 100°E, and 30°S and 55°S.Methods We model 19th century whaling data with boosted regression trees to determine functional responses of whale distribution relative to environmental factors. Habitat suitability maps are generated and we validate these predictions with independent historical and recent sightings. We identify areas of increased risk of ship-strike by integrating predicted whale distribution maps with shipping traffic patterns. We implement predicted ocean temperatures for the 2090-2100 decade in our models to predict changes in whale distribution due to climate change.Results Temperature in the upper 200 m, distance from the subtropical front, mixed layer depth, chlorophyll concentration and distance from ridges are the most consistent and influential predictors of whale distribution. Validation tests of predicted distributions determined generally high predictive capacity. We identify two areas of increased risk of vessel strikes and predict substantial shifts in habitat suitability and availability due to climate change.Main conclusions Our results represent the first quantitative description of the offshore foraging habitat of SRW. Conservation applications include identifying areas and causes of threats to SRW, generating effective mitigation strategies, and directing population monitoring and research efforts. Our study demonstrates the benefits of incorporating unconventional datasets such as historical exploitation data into species distribution models to inform management and help combat biodiversity loss.

The maintenance of long-term associations with particular reef sites is likely to have contributed to the rebuilding of the spiny lobster population (Jasus edwardsii (Hutton) (Decapoda: Palinuridae)) in the Leigh Marine Reserve, in northeast New Zealand. Between 1983 and 1985, 429 lobsters were tagged underwater with western rock lobster tags and antennae tags. Underwater tagging and commercial traps were used to tag a further 737 lobsters with T-bar tags and antennae tags between 1994 and 1996. Twenty-one percent of lobsters resighted (n = 323) between 1983 and 1985 maintained their association with a 15 ha reef inside the reserve for 1-8 years. Site association tended to increase with female size, whereas site association in males was relatively constant until 130 mm carapace length, and then markedly increased. Legalsized lobster abundance fluctuated seasonally, suggesting that a proportion of the population undertook larger-scale movements beyond the reef. This was confirmed during a second tagging programme conducted between 1994 and 1996. About 30% of resighted lobsters (n = 212) moved 0.25-6 km from their tagging site and 20% crossed the boundary, either moving into or out of the reserve. These results indicate that although the Leigh Marine Reserve reduces spatial access to fishing grounds, a proportion of the lobster population moves out of the protected area and becomes susceptible to capture in the adjacent fishery.

Historical research is playing an increasingly important role in marine sciences. Historical data are also used in policy making and marine resource management, and have helped to address the issue of shifting baselines for numerous species and ecosystems. Although many important research questions still remain unanswered, tremendous developments in conceptual and methodological approaches are expected to contribute to a comprehensive understanding of the global history of human interactions with life in the seas. Based on our experiences and knowledge from the “History of Marine Animal Populations” project, this paper identifies the emerging research topics for future historical marine research. It elaborates on concepts and tools which are expected to play a major role in answering these questions, and identifies geographical regions which deserve future attention from marine environmental historians and historical ecologists.

The behaviour and characteristics of J. edwardsii within offshore aggregations in northern New Zealand are described. Groups of up to 200 lobsters were found aggregating beyond the coastal reefs by day, on open sand, amongst beds of the emergent bivalve Atrina zelandica, and around low-lying patch reefs which had little topographical relief. Lobsters within the aggregations displayed behaviour consistent with the use of mutual defence. In areas of open sand, aggregations were circular, with individuals on the perimeter always facing outwards. These lobsters held their stout, spiny antennae upright and used them to fend off potential threats. On patch reefs and around Atrina beds, aggregations were less uniform in shape, and lobsters increased their level of physical protection by clustering against irregularities in the substratum. Offshore aggregations were found over 7 months of the year, but the size and sex ratio of aggregating lobsters varied considerably between seasons. Seasonal peaks in the proportion of male lobsters within the aggregations coincided with peak feeding rates in captive males. The presence of females was not as clearly related to their feeding patterns and probably also reflected behavioural adaptations associated with the carrying of eggs and release of larvae.